Within months of being elected, Faliero attempted a coup d'etat in April 1355, aiming to take effective power from the ruling aristocrats. According to tradition, this came about because the dogaressa, Faliero's second wife, Aluycia Gradenigo, had been insulted by Michele Steno, a member of an aristocratic family,[4] but in a study of doges of Venice Antonella Grignola suggests that Faliero's move was consistent with a prevailing trend in Italian cities to move away from oligarchic government to absolute, dynastic rule.[4]

The plot was badly organised, with poor communication between the conspirators, and was quickly discovered. Faliero pleaded guilty to all charges and was beheaded on 17 April[2][5] and his body mutilated. Ten additional ringleaders were hanged on display from the Doge's Palace in St Mark's Square.[6]

Faliero's picture in the Great Council Hall. The black shroud painted in its place bears the Latin phrase, "This is the space for Marino Faliero, beheaded for crimes."

Faliero was condemned to damnatio memoriae, and accordingly his portrait displayed in the Sala del Maggior Consiglio (Hall of the Great Council) in the Doge's Palace was removed and the space painted over with a black shroud, which can still be seen in the hall today. A Latin language inscription on the painted shroud reads: Hic est locus Marini Faletro decapitati pro criminibus ("This is the space reserved for Marino Faliero, beheaded for his crimes").[4]